JP6506604B2 - Magnetic sensor - Google Patents

Description

  The present invention relates to a magnetic sensor.

  For example, Patent Document 1 discloses a magnetic sensor using a magnetoresistive effect element that can easily and appropriately detect a perpendicular magnetic field component. The magnetic sensor converts the external magnetic field component from the outside into a magnetic field component in the horizontal direction, and a magnetoresistive effect element that exhibits a magnetoresistive effect in which a magnetic layer and a nonmagnetic layer are stacked on a substrate. The magnetoresistive element and the non-contact soft magnetic body for providing the magnetoresistive element with a magnetic field component converted in the horizontal direction. According to the magnetic sensor, a magnetic sensor using a magnetoresistive effect element capable of detecting a perpendicular magnetic field component can be manufactured with a simple configuration, and the magnetic sensor can be manufactured inexpensively, and miniaturization is also promoted. It is supposed to be possible.

International Publication WO2011 / 068146

  In the magnetic sensor described in Patent Document 1, the perpendicular magnetic field from the outside is converted in the horizontal direction by the soft magnetic body, and this is applied to the magnetoresistive element to detect the perpendicular magnetic field. Here, the converted magnetic field component in the horizontal direction is divided into two components of a first side direction and a second side direction opposite to the first side direction in plan view of the soft magnetic body. Therefore, for example, when an element such as a GMR (Giant Magneto Resistive effect) element or the like that detects the difference in the magnetization direction between the fixed magnetic layer and the free magnetization layer by a change in resistance value is used, the element is viewed in plan Depending on whether it is placed on the first side direction or the second side direction in the case, it is possible to configure that the resistance value change is output in the opposite direction to the same external magnetic field input. That is, the bridge circuit can be extremely easily configured by combining the elements arranged in the first side direction and the elements arranged in the second side direction.

  By the way, when the element is arranged only in either the first side direction or the second side direction of the soft magnetic body, the other magnetic field is not used, and the element area is wasted, from the viewpoint of detection sensitivity. Not desirable. Therefore, it is desirable to use the element in both the first side direction and the second side direction of the soft magnetic body.

  However, when it is desired to reduce the resistance value of the magnetoresistive element, it is necessary to connect the magnetoresistive elements in parallel, and in such a case, the arrangement condition of the magnetoresistive element and the soft magnetic material is satisfied. It may be difficult to properly wire the magnetoresistive element.

  An object of the present invention is to detect a perpendicular magnetic field using a soft magnetic material, and even when there is a restriction on the relative positional relationship between the magnetoresistive effect element and the soft magnetic material, the magnetoresistive effect element It is an object of the present invention to provide a technology capable of increasing the degree of freedom in wiring layout and reducing the element area, and thus reducing the cost.

In order to solve the above problems, according to a first aspect of the present invention, a substrate, a plurality of magnetoresistance effect elements disposed on the surface of the substrate, and a first wiring disposed on the surface of the substrate An insulating layer covering the magnetoresistive element and the first wiring, a soft magnetic material disposed on the insulating layer, and a second wiring disposed on the insulating layer, wherein the substrate is planar In the case where two directions orthogonal to each other when viewed as a first direction and a second direction, each of the plurality of magnetoresistance effect elements extends in the first direction and is disposed to be separated in the second direction. The soft magnetic body has a first direction extending portion extending in the first direction, and the first direction extending portion is spaced apart in the second direction when viewed in a plan view. The second wiring is disposed between the magnetoresistive elements, and the second wiring is formed on the insulating layer. Is connected to the first wiring through a through-hole which is, the first wiring is connected to an end of each of the first direction of the plurality of magnetoresistive elements, the second wiring, The present invention provides a magnetic sensor disposed around a soft magnetic material disposition area in which the soft magnetic material is disposed .

In the present invention, a substrate, a plurality of magnetoresistance effect elements disposed on the surface of the substrate, a first wiring disposed on the surface of the substrate, and an insulation covering the magnetoresistance effect element and the first interconnection Layer, a soft magnetic material disposed on the insulating layer, and a second wiring disposed on the insulating layer, and the two directions orthogonal to each other in the first direction when the substrate is viewed in plan And the second direction, each of the plurality of magnetoresistance effect elements extends in the first direction and is spaced apart in the second direction, and the soft magnetic body extends in the first direction. And the first direction extending portion is disposed between the magnetoresistive elements which are disposed apart from each other in the second direction, when viewed in a plan view. A wire is disposed in the first distribution via a through hole formed in the insulating layer. Is connected to said first wiring includes a comb-shaped wiring exhibiting comb pattern when viewed in plan, a straight line exhibiting a line pattern in plan view, wherein the straight line is, the comb-shaped interconnection The magnetic sensor is disposed between the comb teeth, and the second wire is connected to the plurality of straight wires across the comb teeth of the comb wire . In this case, a plurality of the magnetoresistance effect elements may be connected in parallel by the comb-shaped wiring, the linear wiring, and the second wiring. A bridge circuit can be configured by connecting the comb-shaped wiring, the plurality of magnetoresistive elements, the linear wiring, and the second wiring.
The magnetoresistive effect element may be disposed in the vicinity of both end portions in the second direction of the first direction extending portion in a plan view.

  The soft magnetic body has a second direction extending portion extending in the second direction, and both ends in the first direction of the first direction extending portion are short-circuited by the second direction extending portion, A closed magnetic path may be configured by the one-direction extending portion and the second direction extending portion. The soft magnetic body may convert a perpendicular magnetic field component from the outside into a magnetic field component in the horizontal direction, and apply the magnetic field component converted in the horizontal direction to the magnetoresistive element.

  Note that the above summary of the invention does not enumerate all the necessary features of the present invention. In addition, a subcombination of these feature groups can also be an invention.

FIG. 2 is a plan view of the magnetic sensor 100. FIG. 2 is a partial cross-sectional view of a magnetic sensor 100. It is the top view which expanded and showed a part of magnetic sensor 100. FIG. An AA line sectional view in Drawing 3 is shown.

  Hereinafter, the present invention will be described through the embodiments of the invention, but the following embodiments do not limit the invention according to the claims. Moreover, not all combinations of features described in the embodiments are essential to the solution of the invention.

  FIG. 1 shows a plan view of the magnetic sensor 100. FIG. FIG. 2 is a partial cross-sectional view of the magnetic sensor 100. In FIG. 2, the exact cross section at the particular location of FIG. 1 is not shown. For convenience of explanation, it is partially conceptualized and shown. In FIG. 1, the first direction and the second direction orthogonal to each other when the substrate 102 is viewed in plan are taken as the x direction and the y direction, respectively, and the direction orthogonal to both the x direction and the y direction is the z direction Do.

  The magnetic sensor 100 includes a substrate 102, a plurality of magnetoresistive effect elements 104, a first wire 106, an insulating layer 108, a soft magnetic body 110, and a second wire 112.

  The substrate 102 is made of a nonmagnetic material. As long as the substrate 102 is a nonmagnetic material, any material may be used. As the substrate 102, a ceramic substrate, a semiconductor substrate, or the like can be exemplified. The plurality of magnetoresistance effect elements 104 are formed on the surface of the substrate 102, and the first wiring 106 is formed on the surface of the substrate 102. The insulating layer 108 covers the magnetoresistive effect element 104 and the first wiring 106, and the soft magnetic body 110 is disposed on the insulating layer 108. The second wiring 112 is formed on the insulating layer 108. The first wiring 106 includes a comb-shaped wiring 106 a that exhibits a comb-shaped pattern in a plan view, and a straight wiring 106 b that exhibits a line pattern in a plan view. The soft magnetic body 110 has a first direction extending portion 110a extending in a first direction (x direction) and a second direction extending portion 110b extending in a second direction (y direction).

  As the magnetoresistive effect element 104, for example, an element such as a GMR (Giant Magneto Resistive effect) element or a TMR (Tunnel Magneto Resistance Effect) element can be exemplified as an element whose resistance value changes according to a magnetic field. For example, when the magnetoresistive effect element 104 is a GMR element, the magnetoresistive effect element 104 is formed, for example, by laminating an antiferromagnetic layer, a fixed magnetic layer, a nonmagnetic layer, and a free magnetic layer in this order from the bottom The surface of the magnetic layer is covered with a protective layer. The magnetoresistive effect element 104 is formed, for example, by sputtering.

  The antiferromagnetic layer is formed of an antiferromagnetic material such as IrMn alloy (iridium-manganese alloy). The pinned magnetic layer is formed of a soft magnetic material such as a CoFe alloy (cobalt-iron alloy). The pinned magnetic layer is preferably formed in a laminated ferrimagnetic structure. The nonmagnetic layer is Cu (copper) or the like. The free magnetic layer is formed of a soft magnetic material such as a NiFe alloy (nickel-iron alloy). The protective layer is Ta (tantalum) or the like. The laminated structure of the magnetoresistive effect element may be another laminated structure.

  The plurality of magnetoresistance effect elements 104 extend in the first direction (x direction) and are juxtaposed apart in the second direction (y direction). The plurality of first direction extension portions 110 a of the soft magnetic body 110 are respectively disposed between the plurality of magnetoresistance effect elements 104 in the second direction (y direction). Moreover, the magnetoresistive effect element 104 is formed in the vicinity of the both ends in the 2nd direction of each 1st direction extension part 110a. FIGS. 3 and 4 are diagrams showing this in detail, and an enlarged view of one of the plurality of first direction extending portions 110a. The soft magnetic body 110 converts a magnetic field in the vertical direction (z direction) in the plan view into a second direction (y direction). By forming the magnetoresistance effect element 104 in the vicinity of both end portions in the second direction of the soft magnetic body 110 (first direction extending portion 110a), the magnetic field in the vertical direction can be effectively captured without loss. At this time, in the two magnetoresistance effect elements 104 arranged in the vicinity of both end portions of a certain first direction extending portion 110a, resistance value changes are output in opposite directions with respect to the magnetic field in the vertical direction (Z direction).

  The first wiring 106 is connected to the end of the magnetoresistive effect element 104 in the first direction (x direction). Here, the plurality of magnetoresistance effect elements 104 are alternately arranged in the Y direction in which resistance changes are outputted in opposite directions with respect to the magnetic field in the vertical direction (Z direction). The output obtained by electrically connecting the magnetoresistive elements 104 in the same direction in which the resistance value changes in the same direction can be increased, and furthermore, the magnetoresistive elements 104 in one direction in which the resistance value changes in the same direction can be electrically The effect of the disturbance magnetic field is reduced by configuring a bridge circuit with the parallel connection and the parallel connection of the magnetoresistive effect elements 104 in the same direction as the resistance change of the other, thereby reducing the detection sensitivity. It can be enhanced. However, since the magnetoresistive elements 104 are alternately arranged in the Y direction in which the resistance change is output in the opposite direction with respect to the magnetic field in the vertical direction (Z direction), the direction of the resistance change is the same In order to electrically connect the resistance effect element 104, the wiring becomes complicated, and the wiring of the wiring on the surface of the substrate 102 becomes long and the wiring area becomes wide, so the overall size of the magnetic sensor can be reduced. There is a problem that it is difficult.

  To solve the above problems, in the magnetic sensor 100 of the present embodiment, the first wiring 106 does not exist in the region where the magnetoresistive effect element 104 is formed, but in the region where the magnetoresistive effect element 104 is formed. It is formed only in the surrounding area. Therefore, the density of the magnetoresistive effect element 104 can be increased, and the size of the entire magnetic sensor can be reduced. As a result, the productivity can be improved and the cost can be reduced.

  In addition, the second wiring 112 is formed around the soft magnetic material disposition region in which the soft magnetic material 110 is disposed, and the second wiring 112 is formed through the through hole 114 formed in the insulating layer 108. It is connected to the wiring 106. Since the second wire 112 is formed in a layer different from the first wire 106, the second wire 112 can be formed across the first wire 106 while maintaining the insulation property. As a result, the wire routing on the surface of the substrate 102 is The length can be shortened, the wiring area can be narrowed, and the size of the entire magnetic sensor can be reduced. Furthermore, the freedom of wiring design can be increased.

  The straight wiring 106b of the first wiring 106 is formed between the comb teeth of the comb wiring 106a, and the second wiring 112 connects the plurality of straight wirings 106b across the comb teeth of the comb wiring 106a. By using the comb wiring 106a, the magnetoresistive effect elements 104 can be easily connected in parallel. Further, by forming the linear wire 106 b between the comb teeth of the comb wire 106 a and connecting the plurality of linear wires 106 b with the second wire 112, restrictions on the arrangement of the soft magnetic body 110 and the magnetoresistive effect element 104 And the parallel connection of the magnetoresistive effect elements 104 can be realized. Further, a bridge circuit can be configured by connecting the comb wiring 106 a, the plurality of magnetoresistance effect elements 104, and the linear wiring 106 b and the second wiring 112.

  Both ends of the soft magnetic body 110 in the first direction of the first direction extending portion 110a are short-circuited by the second direction extending portion 110b, and a closed magnetic path is formed by the first direction extending portion 110a and the second direction extending portion 110b. Ru. By providing the second direction extension portion 110b of the soft magnetic body 110, the influence of the external magnetic field in the lateral direction (x direction or y direction) can be reduced.

  According to the magnetic sensor 100 of the present embodiment, even when there is a restriction in the relative positional relationship between the magnetoresistive effect element 104 and the soft magnetic body 110, the degree of freedom in the wiring layout of the magnetoresistive effect element 104 is enhanced. The area can be reduced. As a result, cost reduction can be realized.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It is apparent to those skilled in the art that various changes or modifications can be added to the above embodiment. It is also apparent from the scope of the claims that the embodiments added with such alterations or improvements can be included in the technical scope of the present invention.

100 Magnetic sensor 102 Substrate 104 Magnetoresistance effect element 106 First wiring 106a Comb wiring 106b Straight wiring 108 Insulating layer 110 Soft magnetic material 110a First direction extension 110b: second direction extension portion 112: second wiring
114 ... through hole

Claims (7)

A substrate,
A plurality of magnetoresistance effect elements disposed on the surface of the substrate;
A first wire disposed on the surface of the substrate;
An insulating layer covering the magnetoresistive element and the first wire;
A soft magnetic material disposed on the insulating layer;
And a second wire disposed on the insulating layer,
When the two directions orthogonal to each other are the first direction and the second direction when the substrate is viewed in plan,
Each of the plurality of magnetoresistance effect elements extends in the first direction and is spaced apart in the second direction,
The soft magnetic body has a first direction extending portion extending in the first direction, and when viewed in plan, the first direction extending portion is disposed to be separated in the second direction. Placed between the resistive effect elements,
The second wiring is connected to the first wiring through a through hole formed in the insulating layer ,
The first wiring is connected to an end of each of the plurality of magnetoresistive elements in the first direction,
The magnetic sensor wherein the second wiring is disposed around a soft magnetic material disposition region in which the soft magnetic material is disposed . A substrate,
A plurality of magnetoresistance effect elements disposed on the surface of the substrate;
A first wire disposed on the surface of the substrate;
An insulating layer covering the magnetoresistive element and the first wire;
A soft magnetic material disposed on the insulating layer;
And a second wire disposed on the insulating layer,
When the two directions orthogonal to each other are the first direction and the second direction when the substrate is viewed in plan,
Each of the plurality of magnetoresistance effect elements extends in the first direction and is spaced apart in the second direction,
The soft magnetic body has a first direction extending portion extending in the first direction, and when viewed in plan, the first direction extending portion is disposed to be separated in the second direction. Placed between the resistive effect elements,
The second wiring is connected to the first wiring through a through hole formed in the insulating layer,
The first wiring includes a comb-shaped wiring that exhibits a comb-shaped pattern when viewed in plan, and a straight wiring that exhibits a line pattern when viewed in plan,
The straight line is disposed between the comb teeth of the comb line,
A magnetic sensor, wherein the second wiring connects the plurality of straight wirings across the comb teeth of the comb wiring. A plurality of the magnetoresistive elements are connected in parallel by the comb-shaped wiring, the straight wiring and the second wiring.
The magnetic sensor according to claim 2 . A bridge circuit is configured by connecting the comb-shaped wiring, the plurality of magnetoresistive elements, the linear wiring, and the second wiring.
A magnetic sensor according to claim 2 or claim 3 . The magnetoresistive effect element is disposed in the vicinity of both end portions in the second direction of the first direction extending portion in a plan view.
The magnetic sensor according to any one of claims 1 to 4. The soft magnetic body has a second direction extending portion extending in the second direction;
Both ends of the first direction extending portion in the first direction are short circuited by the second direction extending portion,
A closed magnetic field path is constituted by the first direction extending portion and the second direction extending portion.
The magnetic sensor according to any one of claims 1 to 5 . The soft magnetic material converts an external perpendicular magnetic field component into a horizontal magnetic field component, and applies the horizontal converted magnetic field component to the magnetoresistive element.
The magnetic sensor according to any one of claims 1 to 6 .

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